1. Technical Field
This invention relates in general to computer processor sockets and in particular to a computer processor socket with enhanced electrical grounding capabilities. Still more particularly, the invention relates to devices and methods for enhancing the electromagnetic grounding capabilities of computer processor sockets that utilize heat dissipation equipment.
2. Description of the Related Art
As the speed or frequency of computer processors increases, so do the electromagnetic (EM) emissions that interfere with computer operations. Thus, maintaining EM emissions within acceptable or legal limits has become a greater challenge to computer system designers. Unfortunately, as socketed processors approach speeds in the range of 1 GHz and beyond, complex emissions and shielding effectiveness relationships develop between the processor and its associated heat dissipation device regarding the number and location of grounding points therebetween.
Present EM mitigation schemes include utilizing direct grounding pins and/or planes in the processor and socket assembly, along with corresponding grounding paths in the planar board. These grounding features are typically augmented with additional external grounding points (e.g., wires, clips, shields, etc.) as needed. Unfortunately, using existing grounding methods to control the emissions of high speed processor assemblies is predicted to have several disadvantages. For example, increasing the complexity of grounding schemes will potentially require iterative evaluation during product development, and testing cannot be reasonably accommodated given the short product development cycle. If a grounding scheme is found to be insufficient, it is difficult and time-consuming to make a change and retest the solution, due to the need for changes to the planar board design and the associated components. If a processor change is implemented (e.g., clock frequency change, upgrade, or other change), the previous grounding method may not work. If the design or availability of a heatsink changes, the existing grounding components (e.g., wires, clips, shields) are unlikely to fit the substitute heatsink, and additional time and effort will be needed to accommodate it. Furthermore, the grounding scheme for the processor and heatsink assembly is typically planar-dependent and requires a unique grounding solution for each system within which it is installed.
Accordingly, it is an object of the invention to provide an improved computer processor and socket assembly.
It is an additional object of the invention to provide a computer processor and socket assembly with enhanced electrical grounding capabilities.
Still another object of the invention is to provide devices and methods for enhancing the electromagnetic emissions grounding capabilities of computer processor and socket assemblies that utilize heat dissipation equipment.
The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings.
A socket for a computer processor has a base with grounding holes and signal holes. Each hole contains a pin for electrical interconnection with a circuit board. The socket also contains a grounding device extending around its perimeter. The grounding device has flexible wiping members on its upper end that are joined together to form a continuous ring above the base. Alternatively, the wiping members may also be formed as discrete members. When a processor is mounted to the top of the socket, the wiping members extend slightly above the processor. The heatsink mounted on top of the processor engages the wiping members which are spring-biased against its lower surface to form an electrical ground. Since the wiping members extend completely around the perimeter of the socket, a continuous electrical ground interface is formed between the heatsink and the socket. The lower ends of the grounding device are electrically interconnected with the socket grounding pins which are grounded to the board. Alternatively, the lower ends of the grounding device may be spring-biased against grounding pads on the surface of the circuit board.